Canst thou put a hook into his nose - Or rather, a "rope," or "cord." The word used here (אגמון 'agmôn) means "a caldron," or "kettle" Job 41:20, also a reed, or bulrush, growing in marshy places, and thus a rope made of reeds, a rush-cord. The idea is, that he could not be led about by a cord, as tame animals may be. Mr. Vansittart, however, supposes that the words here are expressive of ornaments, and that the allusion is to the fact mentioned by Herodotus, that the crocodile was led about by the Egyptians as a divinity, and that in this state it was adorned with rings and various stately trappings. There can be no doubt that such a fact existed, but this does not accord well with the scope of the passage here. The object is to impress the mind of Job with a sense of the strength and untamableness of the animal, not to describe the honors which were paid to it.
Or bore his jaw through with a thorn - Or with a ring. The word here properly means a thorn, or thorn-bush, Job 31:40; Proverbs 26:9; and then also a ring that was put through the nose of an animal, in order to secure it. The instrument was probably made sharp like a thorn or spike, and then bent so as to become a ring; compare Isaiah 37:29. Mr. Bruce, speaking of the manner of fishing in the Nile, says that when a fisherman has caught a fish, he draws it to the shore, and puts a strong iron ring into its jaw. To this ring is fastened a rope by which the fish is attached to the shore, which he then throws again into the water. "Rosenmuller."

Canst thou put a hook onto his nose? - Canst thou put a ring in his nose, and lead him about as thou dost thine ox? In the East they frequently lead thy oxen and buffaloes with a ring in their noses. So they do bulls and oxen in this country.
Bore his jaw through with a thorn? - Some have thought that this means, Canst thou deal with him as with one of those little fish which thou stringest on a rush by means of the thorn at its end? Or perhaps it may refer to those ornaments with which they sometimes adorned their horses, mules, camels, etc.

Canst thou put an hook into his nose? or (m) bore his jaw through with a thorn?
(m) Because he fears lest you should take him.

Canst thou put an hook into his nose?.... Or a rush, that is, a rope made of rushes; for of such ropes were made, as Pliny (g) affirms;
or bore his jaw through with a thorn? as men do herrings, or such like small fish, for the convenience of carrying them, or hanging them up to dry; the whale is not to be used in such a manner: but the Tentyritae, a people in Egypt, great enemies to crocodiles, had methods of taking thorn in nets, and of binding and bridling them, and carrying them as they pleased (h).
(g) Nat. Hist. l. 19. c. 2. (h) Strabo. Geograph. l. 17. p. 560. Aelian. de Animal. l. 10. c. 21. Plin. Nat. Hist. l. 8. c. 25.

hook--rather, "a rope of rushes."
thorn--rather, a "ring" or "hook." So wild beasts were led about when caught (Isaiah 37:29; Ezekiel 29:4); fishes also were secured thus and thrown into the water to keep them alive.

Thorn - Or, with an iron hook, or instrument as sharp as a thorn; wherewith thou usest to carry little fishes.